[2002-03-19] Portable hole table

First prototype of the Portable Hole Table.  Moire patterns are an artifact of the imaging process.

This is an end- or bedside-table which exploits the optical illusion known as a barbershop mirror to create the effect of an endless hole, appearing much deeper than the table itself. Its construction is illustrated below.

Cross-section of portable hole prototype showing major components.

Within the circumference of a section from a 24"-diameter fiber drum (A, light brown), a one-way circular mirror (B, light blue) is positioned parallel and opposite to a regular opaque mirror of the same size and shape (C, dark blue). The one-way mirror is positioned with its reflective surface oriented downwards, so that its rearward tranparent surface serves as the top of the table. The regular mirror is positioned opposite, with its reflective surface oriented upward. Light, emitted by a doubled length of rope light (D, yellow) concealed within a length of plastic pool-vacuum hose (E, orange), is trapped within the resultant reflective chamber. The image of the glowing plastic tube is thus repeatedly reflected back and forth between the upper and lower mirrors. Because the upper mirror is partially transparent, however, some light is lost during each cycle. This accounts for the attenuation in brightness with each successive image, and for the fact that the images are visible at all.

Looking down into infinity in the depths of the portable hole.

The illusion works best when the table is turned on at night, in a darkened room, but is still impressive in the daytime, under full room lighting conditions. Our prototype has been set up with an appliance timer to automatically turn it on around sundown, and off again after everyone's gone to bed. It serves well as an end table and, because it's on casters, as an improptu TV-tray. And it never fails to attract attention from guests.

last modified 2002-03-19